More standard support for cross-compilation (--host only, no --enable-cross)

2 files changed, 39 insertions, 20 deletions

diff --git a/INSTALL b/INSTALL
index 32c85a7..0aa3b7f 100644
--- a/INSTALL
+++ b/INSTALL
@@ -39,20 +39,30 @@ before the "make install" phase. It will shave a few bytes off them.
 
  Controlling a build process via environment variables is a big and
 dangerous hammer. You should try and pass flags to configure instead;
-nevertheless, the standard environment variables are recognized.
+nevertheless, a few standard environment variables are recognized.
 
- The value of the CROSS_COMPILE environment variable will prefix the
-building tools' names. The --enable-cross option is preferred, see
-"Cross-compilation" below.
- 
  If the CC environment variable is set, its value will override compiler
-detection by configure.
+detection by configure. The --host=HOST option will still add a HOST-
+prefix to the value of CC.
 
  The values of CFLAGS, CPPFLAGS and LDFLAGS will be appended to flags
 auto-detected by configure. To entirely override the flags set by
-configure instead, use make -e.
+configure instead, use make variables.
+
+
+* Make variables
+  --------------
+
+ You can invoke make with a few variables for more configuration.
 
- The Makefile supports the DESTDIR convention for staging.
+ CC, CFLAGS, CPPFLAGS, LDFLAGS, LDLIBS, AR, RANLIB, STRIP, INSTALL and
+CROSS_COMPILE can all be overridden on the make command line. This is
+an even bigger hammer than running ./configure with environment
+variables, so it is advised to only do this when it is the only way of
+obtaining the behaviour you want.
+ 
+ DESTDIR can be given on the "make install" command line in order to
+install to a staging directory.
 
 
 * Shared libraries
@@ -90,9 +100,8 @@ configure with a precomputed sysdeps directory, containing valid
 sysdeps values for your target.
 
  Use the --with-sysdeps=DIR option to specify DIR as a sysdeps
-directory for your target. Also use the --enable-cross=PREFIX option
-to specify a cross-compiling PREFIX for your toolchain's binaries,
-or simply --enable-cross if your default toolchain is a cross-compiler.
+directory for your target. Also use the --host=HOST option, HOST being
+the triplet for your target.
 
  If you know the peculiarities of your target system, you can build
 a sysdeps directory by hand. However, a much easier, and recommended,
@@ -104,11 +113,13 @@ purposes are available at Aboriginal Linux: http://landley.net/aboriginal/
 skarnet.org or on third-party sites.
 
  Once you have gathered your sysdeps, for any skarnet.org package:
+ * make sure the binaries of your cross-toolchain (HOST-gcc, HOST-ld,
+HOST-ar, etc.) are accessible via your PATH environment variable
  * give the correct --with-sysdeps option to ./configure
- * give the correct --enable-cross option
+ * give the correct --host option
  * for --prefix, --bindir and other paths, always use the run-time path
  * to install the cross-compiled package in a staging directory /your/stage,
-   perform "make install DESTDIR=/your/stage/"
+   perform "make install DESTDIR=/your/staging/directory"
 
 
 * The slashpackage convention
diff --git a/configure b/configure
index dfaa30d..a638a89 100755
--- a/configure
+++ b/configure
@@ -35,7 +35,6 @@ Optional features:
   --disable-shared              do not build shared libraries [enabled]
   --disable-static              do not build static libraries [enabled]
   --enable-slashpackage[=ROOT]  assume /package installation at ROOT [disabled]
-  --enable-cross=PREFIX         prefix toolchain executable names with PREFIX [none]
 
 $package options:
   --enable-libc-replacements    use independent low-level primitives [disabled]
@@ -202,7 +201,7 @@ addlibspath=''
 addlibdpath=''
 vpaths=''
 vpathd=''
-cross="$CROSS_COMPILE"
+build=
 
 
 for arg ; do
@@ -225,9 +224,6 @@ for arg ; do
     --enable-slashpackage=*) sproot=${arg#*=} ; slashpackage=true ; ;;
     --enable-slashpackage) sproot= ; slashpackage=true ;;
     --disable-slashpackage) sproot= ; slashpackage=false ;;
-    --enable-cross=*) cross=${arg#*=} ;;
-    --enable-cross) ;;
-    --disable-cross) cross= ;;
     --enable-libc-replacements|--enable-libc-replacements=yes) replacements=true ;;
     --disable-libc-replacements|--enable-libc-replacements=no) replacements=false ;;
     --enable-egd=*) egd=${arg#*=} ;;
@@ -246,8 +242,9 @@ for arg ; do
     --disable-force-devr|--enable-force-devr=no) forcedevr=false ;;
     --with-default-path=*) defaultpath=${arg#*=} ; dpathorig=false ;;
     --without-default-path) defaultpath=$ddefaultpath ; dpathorig=true ;;
-    --enable-*|--disable-*|--with-*|--without-*|--*dir=*|--build=*) ;;
+    --enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
     --host=*|--target=*) target=${arg#*=} ;;
+    --build=*) build=${arg#*=} ;;
     -* ) echo "$0: unknown option $arg" ;;
     *=*) ;;
     *) target=$arg ;;
@@ -308,6 +305,11 @@ if $slashpackage ; then
 fi
 
 # Find a C compiler to use
+if test -n "$target" && test x${build} != x${target} ; then
+  cross=${target}-
+else
+  cross=
+fi
 echo "Checking for C compiler..."
 trycc ${cross}${CC}
 trycc ${cross}gcc
@@ -326,7 +328,13 @@ else
 fi
 
 echo "Checking target system type..."
-test -n "$target" || target=$($CC_AUTO -dumpmachine 2>/dev/null) || target=unknown
+if test -z "$target" ; then
+  if test -n "$build" ; then
+    target=$build ;
+  else
+    target=$($CC_AUTO -dumpmachine 2>/dev/null) || target=unknown
+  fi
+fi
 echo "  ... $target"
 
 tryflag CPPFLAGS_AUTO -std=c99